Read a single line (bytes upto a LF or CRLF). After the whole line has arrived, the $callback will be invoked with the received line as parameter. that line is terminated by a LF (\n), even when the file contains CRLF or CR endings.

This is called when an end-of-file condition is present on the handle. Like muxInput(), it is also passed a reference to the input buffer. You should consume the entire buffer or else it will just be lost.

Called when new input has arrived on the input. It is passed a reference to the input $buffer. It must remove any input that it you have consumed from the $buffer, and leave any partially received data in there.